Accessibility: Inclusion in visualization

Elizabeth King
Kevin Middleton

Plots are a visual medium

Claus Wilke / ggridges

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Color considerations

  • Everyone sees color slightly differently
  • Challenges distinguishing colors impact a large proportion of people
    • Probably ~10%
    • X-linked
  • Resist stereotypical coloration

R Packages

Accessible palettes

Checking a plot

Checking a plot: colorblindr

library(colorblindr)
cvd_grid(EF_bar)

Checking a plot: colorblindr

Checking a plot: colorBlindness

library(colorBlindness)
cvdPlot(EF_bar)

Checking a plot: colorBlindness

Recoloring

library(easystats)
EF_bar2 <- EF_bar +
  scale_fill_OkabeIto(name = "Upstream /\nDownstream")
EF_bar2


Scale for 'fill' is already present. Adding another scale for 'fill', which will replace the existing scale.

Recoloring

Checking a plot: colorblindr

Shape considerations

  • Most useful when color is not an option
    • Color page charges in journals
  • Make the shapes as different as possible

Comparing shapes

Size considerations

  • Size by area (default) or radius
    • Humans are better at area
  • Difficult to distinguish finely between sizes
    • “large” vs. “small”
  • Set the range to control the output scale

Comparing size

Linetype considerations

  • At most 2-3 different line types are easily distinguishable
  • "solid", "dotted", "dashed"

Comparing linetype

Alpha considerations

  • Difficult to distinguish finely between transparency
  • Most often to reduce overplotting in scatter plots